抄録
To evaluate the effect of glucocorticoid on fever induced by inflammation within the peritoneal cavity, we observed core temperature (Tc) in Wistar strain rats given LPS or cytokines (IL-1, TNF, IFN) with or without methylpredonisolone succinate (MP). Tc was recorded in free moving animals using a telemetry system. Vagal afferent nerve activities in response to an administration of LPS (100 μg/kg) increased markedly in intact rats under urethan anesthesia. When animals were given LPS, a marked increase in nocturnal Tc was found. The LPS-induced hyperthermia was abolished completely by the combined hepatic vagotomy with bilateral gastric vagotomy. Tc in rats given not only IL-1 but also TNF increased significantly.Such fever induced by not only LPS but also IL-1 or TNF were prevented completely by a pretreatment with 30mg/kg MP given into the peritoneal cavity before the pyrogenic challenge. These data suggest 1) that afferent signals from the hepatic and gastric branch of the vagus nerves to the brain play an important role in the transmission of an inflammatory signal concerning febrile response, and 2) that MP ameliorate the LPS-evoked fever within the peritoneal region, and 3) that fever induced by either IL-1 or TNF as well as the LPS-evoked fever might be triggered by glococorticoid-sensitive inflammatory processes via another febrific cytokines or prostaglandins yielded within gastrointestinal region. [J Physiol Sci. 2007;57 Suppl:S240]
